Hull For Sailing Craft Whereof The Bottom Enables Water Gliding Performances To Be Enhanced

ABSTRACT

A hull ( 1 ) for sailing craft enables water gliding performances to be enhanced. The hull ( 1 ) for a sailing craft includes a bottom ( 2 ) which has a particular profile. The bottom ( 2 ) includes a rail ( 3 ) shaped from the stem up to the transom, the rail ( 3 ) being formed by a flat axial sole ( 6 ) linking two parallel passageways of the stem to the transom, of similar width, of similar depth of the water inlet at the transom exit, the passageways derived from the sole ( 6 ) have a cross-sectional profile on either side of the sole ( 6 ) to form two V-shaped inclined planes ( 9, 10 ) and are terminated by two arcs of a quarter circle which are further extended by two other inclined parts ( 13, 14 ) forming another V-shape less inclined than the first and leading to the upper works ( 15, 16 ). The invention is applicable to boats.

The invention concerns a hull for sailing craft enabling water-glidingperformances to be enhanced.

The hull according to the invention has a bottom with a particularprofile consisting of a rail shaped from the stem to the transom.

Depending on the applications and the size of the sailing craft, thebottom can be adapted to incorporate one or more profiled rails.

The hull is more especially intended for craft with one or more motors.

The hull according to the invention avoids water spraying on the portand starboard sides.

The hull recovers this stream of water mixed with air bubbles. This massis therefore compressible and is a good absorber of impacts on thehulls.

This stream, which is directed exclusively aft of the transom, ensuresfast uplift.

The friction surface of the hull on the water is clearly decreased, andthis increases the speed of the craft for the same power.

Compared to a conventional hull, fuel consumption is divided by two forthe same speed after uplift has occurred.

This eliminates the wave created by a conventional hull and the energyof this wave channeled under the hull with passageways improves thespeed, the comfort (blocking of air bubbles) and behaviour at sea(direction and roll) thanks to the passageways.

The state of the art can be defined by the following patents:

-   -   DE 4210546: the hull has a tapered nose section, a middle        section and an aft section; each section is made of two        symmetrical lateral sections joined at the keel weld line; a        poop completes the hull; the mid-section can be cast from a        single mould; the gunwales are formed in an edge in order to        link the deck and the cabin; the lateral sections have an        inclined profile under the hull and have an enveloped line        midway from the sides to provide a streamlined profile and        stiffness. No separate cross-piece is required.        USE/ADVANTAGE—small light craft, rowing boat, dinghy. Minimal        use of stainless steel, low-cost construction, which does not        require the use of crosspieces.    -   U.S. Pat. No. 4,875,425: the invention describes a hull form for        a vessel which hull form is deep-V based and is constructed and        arranged for use in a displacement mode; the hull includes a bow        section which incorporates a plurality of lateral grooves or,        alternatively, a single lateral formation and which extends        below the base or datum line of the hull in a streamlined        teardrop configuration; preferably, the hull has deep-V deadrise        angles whose magnitude in the region of the transom of the hull        is not less than 20%; the surfaces extending between the keel        and the length of the water line are non-planar and have        developable convex and concave geometry, all the lines of the        aft parts of the hull have a negative inclination between        substantially ½ and substantially 4. The invention enables the        known advantages of deep-V based hull forms to be used in        displacement mode vessels having relatively large displacements        where, heretofore, “round-bilge” hull forms very greatly        predominated.    -   JP-600421187: SUBJECT: To eliminate the creation of stem waves        and reduce the resistance to pressure of the wave by arranging        symmetrical slats in the vicinity of the draught line and by        eliminating the swirl of the stem waves with the point of the        swirl produced by the said slats. COMPOSITION: A triangular        symmetrical slat having a streamlined cross-section is fixed in        the vicinity of the hull draught line. The aforementioned slat        extends forward to the right and to the left of the bow; The        rear position and the width of the slat are designed so that the        edge of the slat will come close to the front edge of the stem        wave region to be generated as the hull moves forward; as the        hull progresses in direction (i), a circulation stream is        generated around the cross-section of the slat and isolated from        the end of the slat to create the point of the swirl; given that        the rotary direction of the point of the swirl is reversed        relative to the rotation of the swirl created by the pressure of        the wave, they will interact to cancel the swirl created by the        pressure of the wave.    -   U.S. Pat. No. 5,522,333: the invention describes in a catamaran        boat, with a propulsion system, and main hull positioned to        travel above the water surface, the hull extending        longitudinally forward, the combination comprising: two        pontoons, each spaced below the main hull, the pontoons        extending forwardly; support means carried by the main hull and        carrying the pontoons, whereby the pontoons are at least mostly        submerged below the water surface when the boat is loaded and at        rest; the pontoons having associated chimes positioned to allow        the pontoons to plane on the water surface at the typical        planing speeds of the boat; the support means having a        streamlined leading edge structure and upper sponson structure;        and the support means having lateral thickness at a longitudinal        location spaced at a level above the pontoons and which is less        than the maximum width of each of the pontoons at the        longitudinal location.    -   GB-2.383.779: a vessel has a hull, the sided of which in        cross-section form a “V” shape with each side extending in a        single plane to meet the other at the longitudinal central axis        of the vessel; the vessel also has a keel which extends along        the length of the hull and extends down from the point where the        two sides meet; the angle (Ω, FIG. 4) formed between each side        of the hull and the keel is equal to 120°; this arrangement        provides the vessel with improved buoyancy, stability and        streamlining, when compared to conventional hull shapes.    -   US-2005/34647: This invention is a specific technology which        incorporates mechanical engineering and streamlining in order to        allow the lower aft part of the hull of the vessel to fluctuate        upwards and downwards in order to counterbalance the surface of        the water and to stabilize the movement of the vessel when this        is navigating; The invention also uses hinges in order to        effectively assemble the poop and prow hulls and install shock        absorbers during the design process in order to dampen the        impact of external factors and streamline the overall movement        of the vessel when this is moving.    -   FR-2.765.180: The technical field of the invention is        shipbuilding, more particularly the construction of ship hulls;        It concerns a monohull with rear stabilizers, also called        pseudo-trimaran, of a high speed vessel, comprising a central        float and two shorter lateral floats, located towards the rear        of the central float and linked thereto by streamlined linking        arms; According to the invention, the hulls of the three floats        are always partially immersed whatever the speed, the hull of        the lateral floats comprising thin adjustable immersed keels and        the thickness ratio of the three underwater hulls is between        0.25 and 0.35, with a length over width ratio of between 12 and        20 and a ratio of the central hull length to the length of the        lateral hulls of between 2.5 and 4.5.    -   U.S. Pat. No. 4,932,347: A jet ski hull comprising upper and        lower sections joined along a peripheral edge which edge is        arranged to extend above the nominal waterline. According to the        present invention, the lower hull section comprises:    -   1) a central section extending from the bow of the ski to the        stern thereof,    -   2) a concave section on each side of the central section,    -   3) a pair of sidewalls joined to the upper hull section of the        peripheral edge and extending downwardly and inwardly from the        peripheral edge and    -   4) a transition section joining the lower portion of each        sidewall to a respective concave section. Each concave section        defines a channel extending substantially the length of the hull        for channeling water therethrough to prevent the hull from        skidding during turns.    -   In this patent, the central inclined planes do not terminate in        two quarter-circle profiles.        The hull for sailing craft has a bottom which has a special        shape, the bottom is characterized by at least one rail shaped        from the stem to the transom, the said rail being formed of a        flat axial sole linking two parallel passageways from the stem        to the transom, of similar width, similar depth of water inlet        zone at the exit from the transom, the passageways from the sole        having a cross-sectional profile on either side of the sole to        form two V-shaped inclined planes and terminated by two arc of        quarter-circle profiles which are further extended by two other        inclined planes forming a second V shape less inclined than the        first and leading to the upper works, terminating in two flat        parts on the said gunwales

According to one embodiment, the width of the passageways variesaccording to the weight of the hull and the sailing craft application,depending on whether this is designed primarily for speed or not.

The width of the aforesaid passageways is dimensioned to represent ⅓ to40% the width of the hull.

The two V-shaped inclined planes of the passageways are perfectlystraight up to the beginning of the arcs of circle which form arches ofthe passageways.

The arches of the passageways form a quarter arc of a circle so that thecentral water stream and the air bubbles are well contained up to therear of the hull, thus ensuring better sliding.

The two V-shaped inclined planes of the passageways are connected attheir base by a flat longitudinal sole whose width accounts forapproximately 6 to 10% of the total width of the two passageways.

According to a preferred embodiment, the flat part at the bottom of theV shape of the passageways acting as sole has a width equal 10% of thetotal width of the two passageways.

This sole begins progressively from the stem in order to provide auniform width of water inlet.

The aforementioned sole is the lowest part of the hull profile.

According to a preferred embodiment, the aforementioned sole isreinforced so as to absorb shocks.

The two inclined planes forming the central V shape of the passagewayshave to be inclined to form a central V shape which narrower than thetwo other inclined planes which form the second V.

The angle of the inclined planes forming the V shape of the rail liesbetween 40° and 60°.

The angle of the inclined planes forming the V shape of the hull bottomis between 55° and 75°.

There is a difference between the two Vs of approximately 15°.

The rail passageways are parallel from the stem to the transom of thehull.

The rail passageways are the same width from the stem to the transom ofthe hull.

The passageways have the same depth of water inlet zone up to thetransom exit.

The depth of the arch of the rail passageways is approximately 8 to 14%of the total width of the rail.

The depth of the arch of the rail passageways is 10% of the total widthof the rail.

The passageways have to start at the prow of the hull.

According to another embodiment, the hull comprises two otherpassageways parallel to the first passageways, these second passagewayshaving a cross-sectional profile on both sides of the sole forming twoinclined planes forming a third V shape (V3) less inclined than first Vshape (V1), these two inclined planes of the second passageways, thirdpassageway V shape (V3), are perfectly straight until the beginning ofthe arcs of circles forming the arches of the aforesaid passageways.

The arches of these passageways are twice less deep than the firstpassageways.

The width of the arches of the second passageways is 1/12 to 1/30 of thewidth of the hull.

The width of the arches of the first passageways is 1/24 to 1/60 of thewidth of the hull.

The start of the second passageways is situated at the third length ofthe hull, from the prow to the poop or transom.

The second passageways which form the third V shape (V3) eliminate lastlateral water projections.

The drawings attached are given as examples and are not restrictive.They represent only one embodiment of the invention and will make iteasy to understand.

FIG. 1 is a view of the sailing craft, that is to say a front view of aboat.

FIG. 2 is a view of a boat seen from the side.

FIG. 3 is a view of the hull of a boat seen from below so as tohighlight the rail shaped according to the invention.

FIG. 4 is a sectional view of all the volume of the boat highlighting inparticular the hull section, the rail section and the boat hull bottomsection.

FIG. 5 is a view of the boat seen at the stem.

FIG. 6 is a view according to FIG. 5 with the cut lines highlighting theprofile of the bottom and in particular the profile of the railaccording to the invention.

FIG. 7 is a view in perspective of the hull of the boat highlighting thehull profile and in particular the rail.

FIG. 8 is a view according to FIG. 7 seen from other angle thathighlights this particular shape of the rail.

FIG. 9 is a view in perspective of the hull of the boat, in particularat the level of the stem, and this to highlight the first part of therail, the first part of the guidance passageways, and the first part ofthe sole.

FIG. 10 is a simplified sectional view of the boat hull sectionhighlighting the profile of the bottom and in particular the guidancerail.

FIG. 11 is a view in perspective of the underside of the boat hull seenfrom the prow.

FIG. 12 is a view in perspective highlighting all the hull with the stemin the foreground.

FIG. 13 is a simplified view of the boat seen from the side.

FIG. 14 is a simplified view of the boat seen from below.

FIG. 15 is a cross-sectional view of the second embodiment of the hullaccording to the invention.

FIG. 16 is a front view of the hull seen from the stem highlighting thetrailing lines. It highlights the two passageways on each side.

FIG. 17 is a side view of the hull according to the embodiment shown onFIG. 15.

FIG. 18 is a top view of the hull with its trailing lines.

FIG. 19 is a top and perspective view of the hull.

Hull 1 for sailing craft has a bottom and a special profile.

This bottom 2 is characterized by at least one rail 3 shaped from thestem to transom 5.

Said rail 3 is made of a flat axial sole 6 joining two passageways 7 and8 parallel from stem 4 to transom 5.

These passageways 7 and 8 are of the same width and depth of water inletzone from stem 4 to transom 5.

These two passageways 7 and 8 taken from the axial sole 6 have asectional profile and on both sides of sole 6 form two inclined planes 9and 10 forming first V, V1. These two inclined planes 9, 10 terminate intheir upper part by two profiles forming arc of circle 11 and 12 whichare further extended by two other inclined parts 13 and 14 forming asecond V, V2, less inclined than the first V1, the said inclined parts13, 14 leading to upper works 15 and 16.

These inclined parts 13, 14 leading to upper works 15 and 16 terminatein two flat parts 17 and 18.

Width B of passageways 7, 8 have a dimension which represents ⅓ to 40%of width A of the hull.

The two inclined planes 9 and 10 which form the first V shape V1 ofpassageways 7, 8 are perfectly straight up to the start of profiles 11and 12 in an arc or a circle which forms the arches of passageways 7, 8.

The arches of passageways 7, 8 have a quarter arc of a circle form sothat the central waterstream and the air bubbles are well contained upto the rear of the hull to ensure better sliding.

The mixture of air bubbles and water makes it possible for this mass tobe compressed and therefore better able to absorb impacts.

Thus, the sailing craft absorbs the waves better whether at low speed orhigh speed.

The two V-shaped inclined planes 9 and 10 of the passageways areinterconnected at the base by a sole 6.

This flat longitudinal sole 6 is approximately 6 to 10% of the totalwidth of the two passageways, that is to say B.

According to the embodiment shown on FIG. 4, the width of sole 6accounts for 8% compared to the total width of the two passageways,referenced B on FIG. 4.

This sole 6 begins gradually from stem 4 to provide a uniform width ofwater inlet.

The start of sole 6 can be seen at the level of the stem on FIGS. 9, 11and 12.

Sole 6 can of course be reinforced by various materials in order toabsorb impacts.

This sole 6 can act as the stranding sole.

Two inclined planes 9 and 10 forming the central V shape referenced V1on FIG. 10 forming the central V shape of the passageways has to have agreater inclination to form a central V1 that is narrower than the twoother inclined parts 13 and 14 which form the second V, that is to sayV2 referenced on FIG. 2.

The angle of inclined planes 9 and 10 forming the V shape V1 of the railis between 40° and 60°.

The angle of inclined parts 13 and 14 forming the V shape V2 is between55° and 75°.

As highlights FIG. 4, the difference in the angle β between V1 and V2 isapproximately 15°.

As shown on the various figures, passageways 7, 8 of rail 3 are the samewidth from stem 4 to transom 5.

Passageways 7, 8 are the same depth from the water inlet zone to transom5 exit.

The start of passageways 7, 8 shown in particular on FIG. 12 highlightsthat these have to start at the prow or stem 4.

The depth of the arches of the passageways of the rail is approximately8 to 14% of the total width of the rail, that is to say B.

According to a preferred embodiment, the depths of the arch of thepassageways of the rails is 10% of the total width of the rail, that isto say B.

The sailing craft can be a boat with motor, sailboat, hydroplane, seascooter or jet ski.

FIGS. 15 to 19 highlight an embodiment that includes two otherpassageways 19 and 20, these second passageways 19 and 20 being parallelto the first passageways 7 and 8.

These second passageways 19 and 20 have a cross-section on both sides ofthe sole to form two inclined planes 21 and 22 forming third V shape(V3), these inclined planes 21 and 22 being perfectly straight until tothe start of the arc of circle profiles 23, 24 which form the arches ofpassageways 19 and 20.

The two inclined planes 21 and 22 are less inclined than planes 9 and 10forming the first V shape (V1).

The depths of the arches of these passageways 19 and 20 is twice lessdeep than first passageways 7 and 8, the width of the arches of thesearc of circled profiles 23, 24 of the second passageways is 1/12 to 1/30of widths of the hull.

The start of the second passageways 19 and 20 is situated one-thirdalong the hull from the prow to the poop or transom.

REFERENCES

-   1. Hull-   2. Bottom-   3. Rail-   4. Stem-   5. Transom-   6. Axial sole-   7. Passageway-   8. Passageway-   9. Inclined plane-   10. Inclined plane-   First V shape: V1-   11. Arc of circle profile-   12. Arc of circle-   13. Inclined part Forming V2-   14. Inclined part Forming V2-   Second V shape: V2-   15. 16. Upper works-   17. Flat part-   18. Flat part-   B. Width of passageways-   A. Width of hull (bottom) third V-   β: 15° angle difference in V1 and V2-   Third V shape: V3-   19. Passageway-   20. Passageway-   21. Inclined plane of third V shape (V3)-   22. Inclined plane of third V shape (V3)-   23. Arc of circle profile-   24. Arc of circle profile

1. Hull (1) for sailing craft with a bottom (2) which has a particularprofile, the aforementioned bottom (2) being characterized by at leastone rail (3) shaped from stem (4) to transom (5), said rail (3) beingformed by a flat axial sole (6) linking two parallel passageways (7, 8)from stem (4) to transom (5), of similar width, similar depth of waterinlet at the transom (5) exit, the passageways resulting from sole (6)having a cross-sectional profile on either side of sole (6) to form twoinclined planes (9, 10) forming first shape V (V1) and terminate in twoarc of quarter circle profiles (11, 12) which are further extended bytwo other inclined parts (13, 14) forming another V shape (V2), lessinclined than the first leading to the upper works (15,16).
 2. Hull (1)for sailing craft according to claim 1 characterized in that the widthof the said passageways (7, 8) accounts for ⅓ to 40% of the width ofhull (1).
 3. Hull (1) for sailing craft according to claim 1characterized in that two inclined planes (9, 10) of the first V shape(V1) of passageways (7, 8) are of perfectly straight up to the beginningof arcs of circle (12, 13) which form the arches of passageways (7, 8).4. Hull (1) for sailing craft according to claim 1 characterized in thatthe arches of passageways (7, 8) have an arc of quarter circle form sothat the central water stream and the air bubbles are well contained upto the rear of hull (1), thus ensuring better sliding.
 5. Hull (1) forsailing craft according to claim 1 characterized in that the twoinclined planes (9, 10) of first V shape (V1) of passageways (7, 8) arelinked at their base by a flat longitudinal sole (6) the width of whichaccounts for approximately 6 to 10% of the total width of the twopassageways.
 6. Hull (1) for sailing craft according to claim 1characterized in that the flat part at the bottom of first V shape (V1)of passageways (7, 8) acting as sole (6) has a width equal to 8% of thetotal width of the two passageways (7, 8).
 7. Hull (1) for sailing craftaccording to claim 1 characterized in that sole (6) begins graduallyfrom stem (4) to provide a uniform width of water inlet.
 8. Hull (1) forsailing craft according to claim 1 characterized in that the said soleis the lowest part of the profile of hull (1).
 9. Hull (1) for sailingcraft according to claim 1 characterized in that the two inclined planes(9, 10) forming the first central V shape (V1) of passageways (7, 8) hasto be more inclined to form the first central V shape (V1) that isnarrower than the two other inclined parts (13, 14) which form second Vshape (V2).
 10. Hull (1) for sailing craft according to claim 1characterized in that the angle of the inclined planes forming the Vshape of the rail is between 40° and 60°.
 11. Hull (1) for sailing craftaccording to claim 1 characterized in that the angle of the inclinedplanes (13, 14) forming the V shape (V2) of hull (1) bottom is between55° and 75°.
 12. Hull (1) for sailing craft according to claim 1characterized in that passageways (7, 8) of rail (3) are parallel fromstem (4) to transom (5) of hull (1); passageways (7, 8) of rail (3) arethe same width from stem (4) to transom (5) of hull (1); passageways (7,8) are the same depth from water inlet zone to transom (5) exit. 13.Hull (1) for sailing craft according to claim 1 characterized in thatthe depth of the arches of passageways (7, 8) of rail (3) isapproximately 8 to 14% the total width of the rail.
 14. Hull (1) forsailing craft according to claim 1 characterized in that the depth ofthe arches of rail passageways (7, 8) is 10% of the total width of rail(3).
 15. Hull (1) for sailing craft according to claim 1 characterizedin that the aforementioned hull comprises two other passageways (19, 20)parallel to first passageways (7, 8), these second passageways (19, 20)have a cross-sectional profile on both sides of the sole forming twoinclined planes (21, 22) forming a third V shape (V3) less inclined thanthe first V shape (V1), these two inclined planes (21, 22) of the secondpassageways (19, 20) and third V shape passageway (V3) are perfectlystraight up to the beginning of the arcs of circle (23, 24) which formthe arches of the aforesaid passageways (19, 20).
 16. Hull (1) forsailing craft according to claim 15 characterized in that the depth ofthe arches of these passageways (19,20) is twice less deep than that ofthe first passageways.
 17. Hull (1) for sailing craft according to claim15 characterized in that the width of the arches of these secondpassageways is 1/12 to 1/30 the width of the hull.
 18. Hull (1) forsailing craft according to claim 15 characterized in that the start ofthese second passageways (19, 20) is located one third along the hullfrom the prow to the poop or transom.